Useful Furigana Lens is a handy OCR (Optical Character Recognition) app that detects Kanji from Japanese text captured by your smartphone’s camera and automatically overlays furigana. Whether you’re studying languages, reading, or researching and come across a Kanji whose reading you don’t know, simply point your camera and the furigana will be displayed instantly. This powerful support tool is useful in everyday life, study, and business situations. And it’s free—feel free to download it!

◇◇◇ Download the Full Sudachi Dictionary ◇◇◇
The app uses the Sudachi library to assign furigana to Kanji. The built-in dictionary is small, so we recommend downloading the full version. The full version can be downloaded from the settings.

◇◇◇ App Highlights ◇◇◇
- Instant Furigana Display
Point your camera and the app automatically analyzes the Kanji and overlays furigana in real time. Even if the text contains difficult Kanji, you’ll be able to read it with ease.
- Supports a Wide Range of Text
Not only printed materials and books, but also signs, packaging, and screen text are supported. You can easily look up the reading from study texts or even a sign while you’re out and about.
- Simple Operation
No unnecessary settings are needed. Simply launch the app and point your camera. The on-screen display is clear, so even first-time users will find it easy to use.
- Study Support Function
If you save the Kanji and furigana, you can review them later for study purposes. You can list the characters you want to memorize, check them later, and review them.
- Romaji Mode Available
By default, furigana is displayed in Katakana, but you can also opt to display it in Romaji. Just turn on Romaji mode in the settings.
- Offline Operation
You can use the app offline without an internet connection. (Note: Downloading the full Sudachi dictionary requires an internet connection, but once downloaded, the app works offline.)

◇◇◇ How to Use ◇◇◇
- Launch the App
Tap the Useful Furigana Lens icon on your home screen to launch the app.
- Point Your Camera
After launching, the camera preview appears. Aim your smartphone’s camera so that the text or sign you wish to read fits within the square in the top left corner.
- Automatic Text Detection
The app automatically detects Kanji and processes the furigana. A preview in the top right shows the recognized result, and a list of Kanji with overlaid furigana is displayed in the center of the screen.
- Review the Results
Up to 15 results are displayed simultaneously. Once the list is full, older results are overwritten in order. If you’d like to save characters for later review or study, tap the save button on the left. You can review your history later from the menu in the top right corner.
- Magnify with the Magnifier
Touch the view displaying the results to magnify the text.
- Utilize the History
Saved furigana texts can be accessed anytime from another screen. Each file can be easily deleted or copied, and you can even delete all history from the menu in the top right corner.

Useful Furigana Lens is designed to assist with the reading of Kanji—commonly used in Japanese—thus improving your study efficiency and comprehension. Whether you are a student, a Japanese language learner, or need help with unfamiliar Kanji in business or personal contexts, this reliable tool helps reduce the time you spend struggling with Kanji. Give it a try!